Method of and apparatus for pressing glassware



(N0 Model.)

J. H. OROSK'EY & J." LOOKE; METHOD OF AND APPARATUS FOR PRESSING GLASSWARE.

No. 530,825; Patented Dec. 11,1894.

THE Mumps PETERS 00.. mom-uwa, vwsnmumu, 0. c4

UNITED STATES PATENT OFFICE.

JOHN H. oRosKEY AND JOSEPH Looks, or Prr rsBURc, PENNSYLVANIA.

METHOD-OFF AND APPARATUS FOR PItES'SING GLASSWARE.

SPECIFICATION formingpart of Letters Patent no. 530,825,' dated December Application filed crunemset. strains 513,808. (N omodeld To (ZZZ whom it may concern.-

Be it known that we, JOHN H. CROSKEY and J osEPH LOOKE, citizens of the United States, residing at Pittsburg, in the county of Alleghenyand State: of Pennsylvania, have invented certain new and usefullmprovements in Methods-of and Apparatus for Pressing Glassware; and we do hereby declare the following to be a full, clear, andexact descrip tion of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention has relation to steam or pneumatic articles of glass ware and has for its object the provision of means, for regulating the etfective pressure on the piston of the steam or air cylinder so as-tocause the mold plunger to be moved slowly during the first part of its stroke, and to have its speed and force suddenly increased'wheu the plunger comes in contact with the glass in the mold.

Heret ofore, in steam or pneuinatic' glass presses, the plunger has'had a uniform stroke, the force and speed beingunchanged during its movement toward and on the glass, and hence such motion has'been either too rapid and forcible, the piston or plunger moves rapidly and under great pressure during the entire length of its stroke, the plunger strikes the glass with injurious force and suddenness, and not only greatly interferes with the production of good work but causes injury to the framing and working parts of the press. When the plunger moves slowly throughout its entire stroke the pressure on the glass is not quick enough to meet the necessary requirements, which are that the glass should be pressed rapidly and forcibly. There is, moreover, a loss of time entailed in the slow movement of the plunger in the mold, which interferes with rapid production of the ware the press is intended to make.

Our invention consists in the provision of a method of and means for regulating and controlling the movement of the steam or air piston and plunger, whereby the object of our invention is efiectively accomplished.

In the accompanying drawings, Figure l is a vertical central section of part of a steam glass press embodying the preferred mechanical features of ourinvention. Fig. 2 is a horiglass presses, for pressing hollowor too slow and weak. Whenzontal section through the exhaustand automatic exhaust valve. Fig. 3 is a vertical central section through the exhaust valve. Fig.

tis a side view enlarged of the exhaust pipe and valve, with automaticv mechanism in place. Fig. 5 isa vertical central section of high and low pressure cylinder.

Our inventionis applicableeither to steam, pneumatic, or gas operated presses, but is particularly adapted for steam operated presses and hence our description of the mechanical features relates especially to a steam press, Wejuse steam by preference because it is usually more available andeasier to control than air'or gas, and because we find that the steam exhaust pipe can be used to advantage, the "pressure and speed-controlling valve being connected thereto.

In the drawings A designates the steam cylinder in which works the piston B, to the lower end of the rod 0 of which'is attached the mold plunger D, working in the mold E.

F designates the valve chest, in which work the valves G, G, secured to the valve stem H. Thestem H rises through the top of the valve chest and is connected by a link 'h. to the short arm h of the bell crank lever H, by which the valves are operated. I is the steam inlet to the valve chest, and K, K are the ports leading from either end of the valve chests to the steam cylinder.

L. L are the exhaust'ports leading from the ends of the steam chest to the exhaust pipe M through the branches M, M Inthe branch M atthe bottom of the valve chest is located the controlling valve N fitted in a suitable casing N. The valvechamber isof cylindrical form, the axis being horizontal, and the valve-operating valve is a cylindered block with'a centralopening which registers when open with the bore of the exhaust pipe. The valve-has a spindle or boss 0 which is journaled on a seat in the valve casing and, the stem-O of thevalve passes through a stuffing box P, and has at its outer end a crank arm P, which is coupled by a link P to'the short arm of a lever P fulcrumed on a hangerp, depending from the valve chest. To the long arm of the lever P is adjustably secured a curved cam or horn p. To the piston rod is secured a spring plate Q, which as the piston descends strikes and moves incontact with the horn p',thusforcing the horn and lever outward and causing the valve N to be opened wide. Normally, the valve end stands partly open as shown in Fig. 3 and under such conditions the exhaust is obstructed or cramped so that the descent of the piston is partially'impeded by the back pressure of steam below it. When, however, the valve N is thrown wide open, a full exhaust is permitted and the piston being no longer resisted descends rapidly and forcibly under the pressure of steam above it. Now the position of the spring plate Q is such that this full opening of the exhaust takes place at or about the time the plunger reaches the glass, so that the pressure on the glass is rapid and forcible, while the descent of the plunger before reaching the glass is slow. The automatic operation of the valve N can be eflected by other expedients, having substantially the operation and effect as those described, and it necessary or desirable the valve N may be operated by hand and the automatic features dispensed with.

The adj ustability of the horn 1) permits of the period of full opening of the valve being regulated.

When the plunger after having performed its work, rises, the valve N is restored to its normal position bythe inward swinging of the weighted lever I? and horn p.

R designates a valve in the upper branch of the exhaust, to be used, when desired, to control the exhaust from the upper end of the steam cylinder. I

If desired the automatic or controlling valve may be located in the steam inlet pipein which case, the control of force and speed of the plungeris secured by governing the admission of steam to the steam cylinder, 71. a, by admitting a small supply at first, and, when the plunger reaches the glass, suddenly admitting a full supply.

While we have described a steam cylinder and valve, itis obvious that air or other vapor can be used, under substantially the same conditions, and their use is within the spirit and scope of our invention. It is also within the spirit and scope of our invention to use hydraulic apparatus and force, wherever the same can be used to advantage in operating glass presses.

In Fig. 5, we have shown a modified construction of steam or air cylinders and appurtenances designed and adapted for the purpose of utilizing the exhaust air or steam for the purpose of raising the piston and withdrawing the plunger from the glass. In this construction the cylinder is double, the lower half A being enlarged in diameter, so as to constitute a low pressure cylinder. The piston rod has two heads, B and B, the head B working in the upper cylinder and the head B in the lower cylinder. The valve chest has a by pass exhaust B which, when the valve is lowered, leads the exhaust steam or air from the upper cylinder to the space between the lower heads of the valve, whence it enters the bottom of the lower cylinder by way of the port a, and raises the pistonhead B and with it the piston B, piston rod and plunger. The valve has double heads on each end, so that when the valve is lowered the exhaust fromthe upper cylinder to the lower cylinder is through the spaces between the heads, the main exhaust M being closed by the head on the lower end of the valve rod.

When the valves are raised, the outlet to the upper end of the by pass exhaust is closed, and the outlet to the main exhaust opened. The lower cylinder then exhausts through the main exhaust pipe M and as this takes place when the pistons are descending the valve N is operated as already described. When the valves are raised, as stated, the steam or air inlet is put in communication with the space above the upper piston head and the piston is lowered by the steam or air at high pressure. The by pass exhaust B is provided with a regulating valve b Having described our invention, we claim- 1. The method of operating power glass pressing apparatus, which consists in varying the speed and force of the piston and plunger during their working strokes, so as to cause the plunger to descend slowly until it reaches the glass in the mold, and to then increase its speed of movement.

2. In steam or equivalent power-operated glass presses, the combination with the piston cylinder, and the power supply or exhaust pipe, of a throttle valve, and mechanism substautially as described, comprising a moving part attached to the valve stem and a contacting part attached to the piston rod whereby the said valve is operated automatically during the working stroke of the piston and plunger, so as to periodically increase the effective working pressure. 3. In a glass press, the combination with the steam, or other cylinder, of an exhaust pipe provided with a throttle valve, combined with automatic mechanism substantially as described, comprising a rod or lever on the valve and a tappet on the piston rod adapted to contact with said rod or lever for operating said valve so as to periodically increase the exhaust.

4. In a glass press, the combination with the steam or other cylinder, and the piston and plunger of an exhaust or supply pipe, containing a throttle valve, a crank on the stem of said valve, a lever coupled to said crank, a cam or horn on said lever, and a plate or striker attached to the plunger rod, and arranged and adapted to strike said cam or horn during its descent, and to thereby periodically increase the opening of the exhaust valve.

In testimony whereof we affix oursignatures in presence of two witnesses.

J. H. CROSKEY. JOSEPH LOCKE.

Witnesses:

O. E. SUoooP, II. A. ROBERTS. 

